Question 1
The diagram shows a section through a human heart with the chambers, valves and main blood vessels.
What are the functions of X and Y ?
A.
X
Y
To carry oxygenated blood to the
head and body
To prevent backflow into the aorta
when the ventricle relaxes
To carry oxygenated blood to the
head and body
To prevent backflow into the aorta
when the atrium relaxes
To carry deoxygenated blood to
the lungs
To prevent backflow into the atrium
when the ventricle contracts
To carry deoxygenated blood to
the lungs
To prevent backflow into the atrium
when the ventricle relaxes